Motorola MVME167P, Инструкция по установке и эксплуатации

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Functional Description
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baud). The four serial ports differ functionally because of the limited
number of pins on the P2 I/O connector.
❏
Serial port 1 is a minimum-function asynchronous port. It uses the
RXD, CTS, TXD, and RTS signals.
❏
Serial ports 2 and 3 are full-function asynchronous ports. They use
the RXD, CTS, DCD, TXD, RTS, and DTR signals.
❏
Serial port 4 is a full-function synchronous or asynchronous port
which can operate at synchronous bit rates up to 64K bits per
second. It uses the RXD, CTS, DCD, TXD, RTS, and DTR
signals. It also interfaces to the synchronous clock signal lines.
All four serial ports use EIA-232-D drivers and receivers located on the
main board, and all the signal lines are routed to the P2 I/O connector. The
configuration headers are located on the main board and may be present on
some transition boards. An external I/O transition board is necessary to
convert the I/O connector pinout to industry-standard connectors. For
drawings of the serial port interface connections, refer to the MVME1X7P
Single Board Computers Programmer’s Reference Guide.
Note The MVME167P board hardware ties the DTR signal from the
CD2401 to the pin labeled RTS at connector P2. Likewise, RTS
from the CD2401 is tied to DTR on P2. Therefore, when
programming the CD2401, assert DTR when you want RTS, and
RTS when you want DTR.
The interface provided by the PCCchip2 ASIC allows the 16-bit CD2401
to appear at contiguous addresses; however, accesses to the CD2401 must
be 8 or 16 bits. 32-bit accesses are not permitted. Refer to the CD2401 data
sheet and to the PCCchip2 description in the Programmer’s Reference
Guide for detailed programming information.
The CD2401 supports DMA operations to local memory. Because the
CD2401 does not support a retry operation necessary to break VMEbus
lockup conditions, the CD2401 DMA controllers should not be
programmed to access the VMEbus. The hardware does not restrict the
CD2401 to onboard DRAM.